UV PhotoVap: Demonstrating How a Simple and Versatile Reactor Based on a Conventional Rotary Evaporator Can Be Used for UV Photochemistry

Abstract

We report the use of a simple rotary evaporator as a semi-continuous UV photochemical reactor. By generation of a thin film from the rotation of a flask, better light penetration is achieved, and in this work we used high-power Hg lamps to enable the direct irradiation of molecules with UV light. The intramolecular [2 + 2] photocycloaddition of Cookson’s dione and the intermolecular [2 + 2] photocycloaddition of maleimide with 1-hexyne were used as test reactions to examine the effectiveness of this reactor. High productivities, equivalent to 210 g h–1, were obtained for the simple intramolecular reaction, demonstrating the scalability of the reactor. The effects of flask size, reaction mixture volume, and use of borosilicate or quartz glassware were also investigated.

Scalable Continuous Vortex Reactor for Gram to Kilo Scale for UV and Visible Photochemistry

“…Changing to UV photochemistry, we began by studying the chemistry in the small reactor to by both us and others. 34,37,44 In both the small and the large reactor we employed high powered Hg lamps (1.4 kW or 2 kW units -see ESI for further details). In the small reactor, good results were obtained using a single 1.4 kW lamp, with complete conversion and >99% yield at flow rates of 1-4 mL min -1 ( Table 2, entries 1-4).…”

“…35 Our own contributions have involved the generation of thin films of reaction mixture for more efficient light penetration using either excimer lamps for discrete wavelength excitation, 36 or high powered light sources with a modified rotary evaporator for visible and/or UV photochemistry. [37][38] Of particular relevance to this paper is our recent report of a small-scale visible light reactor 39 which exploited the use of Taylor vortices. 40 In this design, the chemical reactor consists of a transparent cylindrical outer vessel with a second smooth cylinder fitted coaxially inside it.…”

The Right Light: De Novo Design of a Robust Modular Photochemical Reactor for Optimum Batch and Flow Chemistry

“…To enable comparison of PHIL with others in the literature a [2+2]‐cycloaddition reaction (Scheme ) was examined . This reaction, thought to be UV mediated, typically utilizing a Hg lamp (polychromatic 200–580 nm), has predominately been performed in flow, and so this setup was employed by first intent .…”

Reactor Technology Concepts for Flow Photochemistry

“…Just recently, Clark et al . also performed this reaction with their modified lab rotary evaporator photoreactor in batch mode (introduced in Figure ) and achieved a productivity of 210.6 g h −1 …”